nrf52 TWI communication with LIS3DH

RE: nrf52 TWI communication with LIS3DH

Seihan — Sat, 03 Aug 2019 12:56:44 GMT

Thank you for your help.

Finally I solved it by using GCC. The problem with undefined references was somewhere inside the sdk_config.h, I copied one from the twi_master example. The UNPLACED SECTIONS error was only inside SES.

RE: nrf52 TWI communication with LIS3DH

LFanals — Fri, 02 Aug 2019 08:53:10 GMT

Hi Seihan,

The first error suggests me that there is a problem with memory allocation.

Now some questions arise:

- Are you using some kind of BLE communication, or is SoftDevide needed? If so I would suggest to manually allocate enough space. There are some threads that explain it better than me. Right now my configuration of a code that uses BLE looks like this. I am using Segger, in case you use Keil or other softwares menus change but you can configure it as well.

Then, in Segger at least, you should see some bars as these

If your project is huge you may need more memory than the quantity you have available, yet I don't thing it's the case.

- If you aren't using SoftDevice or what I've previously said doesn't work, try to copy paste my code and include all the libraries needed. It worked for me this way, and I don't remember configurating memory space.

I'm not sure that solves your problem, but I hope it works.

RE: nrf52 TWI communication with LIS3DH

Seihan — Wed, 31 Jul 2019 11:16:12 GMT

Hi,

can you please explain how do you got this project to work? I've copied your code in main.c of the twi_sensor example, included all *.h header files in projects properties and added the *.c files in projects explorer. After saving and reloading the project I got this errors:

    Output/Release/Exe/twi_sensor_pca10040.elf section `.nrf_queue' will not fit in region `UNPLACED_SECTIONS'
    region `UNPLACED_SECTIONS' overflowed by 20 bytes
    Output/twi_sensor_pca10040 Release/Obj/nrf_twi_sensor.o: in function `nrf_twi_sensor_reg_read':
    undefined reference to `nrf_twi_mngr_schedule'
    Output/twi_sensor_pca10040 Release/Obj/nrf_twi_sensor.o: in function `nrf_twi_sensor_write':
    undefined reference to `nrf_twi_mngr_schedule'
    Output/twi_sensor_pca10040 Release/Obj/main.o: in function `main':
    undefined reference to `nrf_twi_mngr_init'
Build failed

Thank you in advance,

Hannes

RE: nrf52 TWI communication with LIS3DH

Øyvind — Mon, 08 Jul 2019 12:55:18 GMT

Glad to hear you figured out the issue yourself! 🙂

-Øyvind

RE: nrf52 TWI communication with LIS3DH

LFanals — Mon, 08 Jul 2019 12:37:18 GMT

After a bit of testing I discovered that instead of

LIS2DH12_INSTANCE_DEF(m_lis2dh12, &m_nrf_twi_sensor, LIS2DH12_BASE_ADDRESS_HIGH);

I should have

LIS2DH12_INSTANCE_DEF(m_lis2dh12, &m_nrf_twi_sensor, LIS2DH12_BASE_ADDRESS_LOW);

As the lis2dh12 or lis3dh datasheets explain on the I2C operation, the adress are 7 bits long and the LSB can either be 1 or 0 depending on how is a pin connected, making the address value equal 19 or 18. In my case, 18 was the right choice.

I apologize for the noobie mistake I've made, and I'm gonna keep updating the progress I make.

LFanals